The present invention concerns a spray head, especially for a high-pressure spray gun, comprising a rotary element, which is placed within a central body and through which passes a duct having a spray orifice, and a seal ensuring leak-tightness between the rotary element and the gun.
Patent Application PCT/CH97/00316 discloses a spray head for a high-pressure spray gun, comprising an element of a cylindrical shape, which is mounted rotatably in a central body and through which passes a main conduit. At the end of the conduit is mounted a spray nozzle for delivering a tapered high-pressure fluid jet. Two low-pressure air ducts are prolonged from the central body within the cylindrical-shaped element on either side of the central conduit of the nozzle. The air-jet outlet orifices in the element of cylindrical-shaped element are offset in relation to the inlet orifices in communication with the ducts of the central body.
Patent Application PCT/CH98/00104 discloses a spray head for a high-pressure spray gun, comprising a rotary element, which is placed in a central body and through which passes a duct having a spray orifice. A seal ensures leak-tightness between the rotary element and the gun. The rotary element has, in its central part, a spherical shape capable of cooperating with the seal placed within the central body. Two circular seats are placed on either said of the spherical part bearing on the seats placed on either side of the central body.
The disadvantage of the spray heads known in the prior art is that the slit of the nozzle is at a level substantially equal to or lower than the top of the spray head, which always results in interferences at the outlet of the fluid jet. Moreover, at the moment when work is stopped, the liquid which has been unable to leave the gun falls down around the nozzle. The user is therefore faced with the need to clean it in order to prevent dry paint from accumulating around the slit of the nozzle and on the top of the spray head. The problem becomes even more acute when spray heads with additional air jets are used, since the air jets cause turbulence giving rise to fluid sedimentation deposits on the top of the head. These deposits are particularly troublesome, since they give rise to droplets which may be thrown on to the articles to be treated by the air jets.